Air-break circuit interrupters of the prior art have generally used heavy insulating members for supporting the power-conductor assemblies, as for example, set forth in the U.S. Pat. No. 3,437,554 issued Apr. 8, 1969 to James Gamble and assigned to the assignee of the instant application. Also insulating plates have heretofore been used in the art, as well as other insulating members of plate-like construction. In some instances bushings having flange portions have been passed through suitable apertures provided in metallic frame plates, and the flange portions have been bolted to the peripheries of the holes provided in the metallic-frame members.
As well known by those skilled in the art, air-break circuit interrupters are available in a wide variety of voltage and current ratings. For example, such equipment may be suitable for 15 K.V. voltage, at a current rating, of for example, 1200-amperes, 2,000-amperes, and 3,000-amperes. The articular voltage and current rating supplied, of course, depends upon the requirements of the utility customer, and his particular needs and application of the equipment.